Heretofore, it has been known that 11-unsubstituted, 11-hydroxy or 11-oxodibenz[b,e]oxepin derivative is used for antiinflammatory agents [J. Med. Chem., 21, 633-639 (1978)].
Further, it is known that dibenz[b,e]oxepin derivative wherein substitutents Ra and Rb at 11-position have the following definitions, is employed in the treatment and control of allergic conditions (U.S. Pat. No. 4,282,365).
Ra: H, OH, lower alkoxy, lower alkylthio, lower alkylsulfinyl, lower alkylsulfonyl, arylthio, NH.sub.2, NHCHO or imidazolyl; PA0 Rb: H or lower alkyl; or Ra and Rb taken together are .dbd.0, .dbd.CH--Rc wherein Rc is H or aryl.
Furthermore, it is known that 11-(4-methylpiperazino) dibenz[b,e]oxepin derivative has an anti-asthmatic activity (U.S. Pat. No. 4,396,550, U.S. Pat. No. 4,465,835, EP-A-38564).
It is also known that dibenz[b,e]oxepin derivative having the following formula: ##STR1## wherein Rd and Re are lower alkyl and Rf is lower alkyl or halogen, has an antiasthmatic activity (EP-A-85870).
Dibenz[b,e]oxepin derivative having an antiallergic activity and having the following structural formula: ##STR2## wherein Rg and Rh are alkyl, r is 2 or 3 and Ri is alkyl or halogen is known (JP-A-227879/84).
Dibenz[b,e]oxepin derivative having an antiallergic activity and having the following structural ##STR3## wherein Rj is 4-alkylpiperazino, 3-quinuclidylamino or --Xa--(CH.sub.2)hd s--NR.sub.l R.sub.m wherein X.sub.a is --NH--, --S-- or --O--, s is 2 or 3 and R.sub.l and R.sub.m are alkyl, and R.sub.k is CN, 5-tetrazolyl, CONH.sub.2 or CO.sub.2 R.sub.n wherein R.sub.n is H, alkyl or 1-(ethoxycarbonyloxy)ethyl is known (EP-A-130555).
Doxepin having an antidepressant activity and having the following structural formula is known [Drugs, 13, 161 (1977)]. ##STR4##
Dothiepin having an antidepressant activity and having the following structural formula is known [Arz.-Forsch., 13 1039 (1963); ibid., 14 100 (1964)]. ##STR5##
As the compound having both an antiallergic activity and an antiinflammatory activity, steroids are known.
It is always desired that a novel compound having an antiallergic activity or an antiinflammatory activity be developed.